Gas turbine engines use fuel injectors to inject fuel into a combustor. One type of fuel injector atomizes highly pressurized fuel through a small orifice into the combustion chamber. Another type of fuel injector atomizes fuel at a low pressure using shear forces provided by a gas stream surrounding the injected fuel stream as it enters the combustion chamber. Both types of fuel injectors are designed for the sole purpose of atomizing fuel within the combustion chamber.
There are a variety of combustor configurations, including a reverse flow annular combustor. Reverse flow annular combustors include a liner dividing a combustion chamber, into axially co-flowing exterior (cold, non-combusting) and interior (hot, combusting) annular flows. Apertures and holes are provided in the liner wall to allow cold compressed air (exterior annular flow) into the inner annular section of the combustion chamber, where under admission of fuel a combustion process takes place. An outlet is provided at the end of the inner annular flow path which is connected to a turbine nozzle. The fuel injectors typically include a cylindrical shaped housing having a hemispherical domed end, which extend from the outer annular flow path through the liner and into the inner annular flow path of the combustion chamber. The flow path interior to the liner extends from the liner apertures and holes to the outlet end of the inner annulus such that a considerable amount of gases must flow past the fuel injector housing. The presence of the fuel injector volumes and its effects on the internal combustor aerodynamics can create hotspots and result in undesirable flow and temperature patterns within the combustion volume, i.e., annular/toroidal volume interior to the combustor liner.